Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 167
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Nat Immunol ; 15(3): 239-47, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24487321

RESUMO

Here we found that the transcription repressor DREAM bound to the promoter of the gene encoding A20 to repress expression of this deubiquitinase that suppresses inflammatory NF-κB signaling. DREAM-deficient mice displayed persistent and unchecked A20 expression in response to endotoxin. DREAM functioned by transcriptionally repressing A20 through binding to downstream regulatory elements (DREs). In contrast, binding of the transcription factor USF1 to the DRE-associated E-box domain in the gene encoding A20 activated its expression in response to inflammatory stimuli. Our studies define the critical opposing functions of DREAM and USF1 in inhibiting and inducing A20 expression, respectively, and thereby the strength of NF-κB signaling. Targeting of DREAM to induce USF1-mediated A20 expression is therefore a potential anti-inflammatory strategy for the treatment of diseases associated with unconstrained NF-κB activity, such as acute lung injury.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Proteínas Interatuantes com Canais de Kv/metabolismo , Proteínas Repressoras/metabolismo , Ubiquitina-Proteína Ligases/biossíntese , Fatores Estimuladores Upstream/metabolismo , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Animais , Imunoprecipitação da Cromatina , Cisteína Endopeptidases , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica/imunologia , Immunoblotting , Inflamação/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/genética , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína 3 Induzida por Fator de Necrose Tumoral alfa , Ubiquitina-Proteína Ligases/genética
2.
Mol Cell Proteomics ; 22(12): 100671, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37863319

RESUMO

Nuclear matrix (NuMat) is the fraction of the eukaryotic nucleus insoluble to detergents and high-salt extractions that manifests as a pan-nuclear fiber-granule network. NuMat consists of ribonucleoprotein complexes, members of crucial nuclear functional modules, and DNA fragments. Although NuMat captures the organization of nonchromatin nuclear space, very little is known about components organization within NuMat. To understand the organization of NuMat components, we subfractionated it with increasing concentrations of the chaotrope guanidinium hydrochloride (GdnHCl) and analyzed the proteomic makeup of the fractions. We observe that the solubilization of proteins at different concentrations of GdnHCl is finite and independent of the broad biophysical properties of the protein sequences. Looking at the extraction pattern of the nuclear envelope and nuclear pore complex, we surmise that this fractionation represents easily solubilized/loosely bound and difficultly solubilized/tightly bound components of NuMat. Microscopic analyses of the localization of key NuMat proteins across sequential GdnHCl extractions of in situ NuMat further elaborate on the divergent extraction patterns. Furthermore, we solubilized NuMat in 8M GdnHCl and upon removal of GdnHCl through dialysis, en masse renaturation leads to RNA-dependent self-assembly of fibrous structures. The major proteome component of the self-assembled fibers comes from the difficultly solubilized, tightly bound component. This fractionation of the NuMat reveals different organizational levels within it which may reflect the structural and functional organization of nuclear architecture.


Assuntos
Matriz Nuclear , Proteômica , Matriz Nuclear/metabolismo , Proteoma/metabolismo , DNA/metabolismo , RNA/metabolismo , Núcleo Celular
3.
J Proteome Res ; 23(6): 2265-2278, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38743012

RESUMO

The effect of the parental environment on offspring through non-DNA sequence-based mechanisms, such as DNA methylation, chromatin modifications, noncoding RNAs, and proteins, could only be established after the conception of "epigenetics". These effects are now broadly referred to as multigenerational epigenetic effects. Despite accumulating evidence of male gamete-mediated multigenerational epigenetic inheritance, little is known about the factors that underlie heat stress-induced multigenerational epigenetic inheritance via the male germline in Drosophila. In this study, we address this gap by utilizing an established heat stress paradigm in Drosophila and investigating its multigenerational effect on the sperm proteome. Our findings indicate that multigenerational heat stress during the early embryonic stage significantly influences proteins in the sperm associated with translation, chromatin organization, microtubule-based processes, and the generation of metabolites and energy. Assessment of life-history traits revealed that reproductive fitness and stress tolerance remained unaffected by multigenerational heat stress. Our study offers initial insights into the chromatin-based epigenetic mechanisms as a plausible means of transmitting heat stress memory through the male germline in Drosophila. Furthermore, it sheds light on the repercussions of early embryonic heat stress on male reproductive potential. The data sets from this study are available at the ProteomeXchange Consortium under the identifier PXD037488.


Assuntos
Drosophila melanogaster , Epigênese Genética , Resposta ao Choque Térmico , Proteoma , Espermatozoides , Animais , Masculino , Espermatozoides/metabolismo , Drosophila melanogaster/genética , Resposta ao Choque Térmico/genética , Proteoma/metabolismo , Proteoma/genética , Cromatina/metabolismo , Cromatina/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo
4.
Chromosome Res ; 31(1): 7, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36719476

RESUMO

The homeotic genes or Hox define the anterior-posterior (AP) body axis formation in bilaterians and are often present on the chromosome in an order collinear to their function across the AP axis. However, there are many cases wherein the Hox are not collinear, but their expression pattern is conserved across the AP axis. The expression pattern of Hox is attributed to the cis-regulatory modules (CRMs) consisting of enhancers, initiators, or repressor elements that regulate the genes in a segment-specific manner. In the Drosophila melanogaster Hox complex, the bithorax complex (BX-C) and even the CRMs are organized in an order that is collinear to their function in the thoracic and abdominal segments. In the present study, the regulatorily inert regions were targeted using CRISPR/Cas9 to generate a series of transgenic lines with the insertion of FRT sequences. These FRT lines are repurposed to shuffle the CRMs associated with Abd-B to generate modular deletion, duplication, or inversion of multiple CRMs. The rearrangements yielded entirely novel phenotypes in the fly suggesting the requirement of such complex manipulations to address the significance of higher order arrangement of the CRMs. The functional map and the transgenic flies generated in this study are important resources to decipher the collective ability of multiple regulatory elements in the eukaryotic genome to function as complex modules.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Animais , Drosophila melanogaster/genética , Proteínas de Drosophila/genética , Sistemas CRISPR-Cas , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Sequências Reguladoras de Ácido Nucleico
5.
Chromosome Res ; 31(1): 8, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36725757

RESUMO

The nucleus is a complex organelle that hosts the genome and is essential for vital processes like DNA replication, DNA repair, transcription, and splicing. The genome is non-randomly organized in the three-dimensional space of the nucleus. This functional sub-compartmentalization was thought to be organized on the framework of nuclear matrix (NuMat), a non-chromatin scaffold that functions as a substratum for various molecular processes of the nucleus. More recently, nuclear bodies or membrane-less subcompartments of the nucleus are thought to arise due to phase separation of chromatin, RNA, and proteins. The nuclear architecture is an amalgamation of the relative organization of chromatin, epigenetic landscape, the nuclear bodies, and the nucleoskeleton in the three-dimensional space of the nucleus. During mitosis, the nucleus undergoes drastic changes in morphology to the degree that it ceases to exist as such; various nuclear components, including the envelope that defines the nucleus, disintegrate, and the chromatin acquires mitosis-specific epigenetic marks and condenses to form chromosome. Upon mitotic exit, chromosomes are decondensed, re-establish hierarchical genome organization, and regain epigenetic and transcriptional status similar to that of the mother cell. How this mitotic memory is inherited during cell division remains a puzzle. NuMat components that are a part of the mitotic chromosome in the form of mitotic chromosome scaffold (MiCS) could potentially be the seeds that guide the relative re-establishment of the epigenome, chromosome territories, and the nuclear bodies. Here, we synthesize the advances towards understanding cellular memory of nuclear architecture across mitosis and propose a hypothesis that a subset of NuMat proteome essential for nucleation of various nuclear bodies are retained in MiCS to serve as seeds of mitotic memory, thus ensuring the daughter cells re-establish the complex status of nuclear architecture similar to that of the mother cells, thereby maintaining the pre-mitotic transcriptional status.


Assuntos
Núcleo Celular , Cromatina , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cromatina/genética , Cromatina/metabolismo , Cromossomos/genética , Matriz Nuclear/metabolismo , Mitose
6.
AAPS PharmSciTech ; 25(5): 111, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740666

RESUMO

This in-depth study looks into how artificial intelligence (AI) could be used to make formulation development easier in fluidized bed processes (FBP). FBP is complex and involves numerous variables, making optimization challenging. Various AI techniques have addressed this challenge, including machine learning, neural networks, genetic algorithms, and fuzzy logic. By integrating AI with experimental design, process modeling, and optimization strategies, intelligent systems for FBP can be developed. The advantages of AI in this context include improved process understanding, reduced time and cost, enhanced product quality, and robust formulation optimization. However, data availability, model interpretability, and regulatory compliance challenges must be addressed. Case studies demonstrate successful applications of AI in decision-making, process outcome prediction, and scale-up. AI can improve efficiency, quality, and cost-effectiveness in significant ways. Still, it is important to think carefully about data quality, how easy it is to understand, and how to follow the rules. Future research should focus on fully harnessing the potential of AI to advance formulation development in FBP.


Assuntos
Inteligência Artificial , Química Farmacêutica , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Tecnologia Farmacêutica/métodos , Lógica Fuzzy , Redes Neurais de Computação , Aprendizado de Máquina , Algoritmos
7.
Angew Chem Int Ed Engl ; 63(22): e202403900, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38459961

RESUMO

Maintaining lipid asymmetry across membrane leaflets is critical for functions like vesicular traffic and organelle homeostasis. However, a lack of molecular-level understanding of the mechanisms underlying membrane fission and fusion processes in synthetic systems precludes their development as artificial analogs. Here, we report asymmetry induction of a bilayer membrane formed by an extended π-conjugated molecule with oxyalkylene side chains bearing terminal tertiary amine moieties (BA1) in water. Autogenous protonation of the tertiary amines in the periphery of the bilayer by water induces anisotropic curvature, resulting in membrane fission to form vesicles and can be monitored using time-dependent spectroscopy and microscopy. Interestingly, upon loss of the induced asymmetry by extensive protonation using an organic acid restored bilayer membrane. The mechanism leading to the compositional asymmetry in the leaflet and curvature induction in the membrane is validated by density functional theory (DFT) calculations. Studies extended to control molecules having changes in hydrophilic (BA2) and hydrophobic (BA3) segments provide insight into the delicate nature of molecular scale interactions in the dynamic transformation of supramolecular structures. The synergic effect of hydrophobic interaction and the hydrated state of BA1 aggregates provide dynamicity and unusual stability. Our study unveils mechanistic insight into the dynamic transformation of bilayer membranes into vesicles.


Assuntos
Bicamadas Lipídicas , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Teoria da Densidade Funcional , Interações Hidrofóbicas e Hidrofílicas , Aminas/química , Estrutura Molecular , Água/química
8.
Biochem Biophys Res Commun ; 641: 50-56, 2023 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-36521285

RESUMO

Kyasanur forest disease is a neglected zoonotic disease caused by a single-stranded RNA-based flavivirus, the incidence of which was first recorded in 1957 in the Southern part of India. Kyasanur forest disease virus is transmitted to monkeys and humans through the infected tick bite of Haemophysalis spinigera. Kyasanur forest disease is a febrile illness, which in severe cases, results in neurological complications leading to mortality. The current treatment regimens are symptomatic and supportive, and no targeted therapies are available for this disease. In this study, we evaluated the ability of FDA-approved drugs sofosbuvir (and its active metabolite) and Dasabuvir to inhibit the RNA-dependent RNA polymerase activity of NS5 protein from the Kyasanur forest disease virus. NS5 protein containing the N-terminal methyl transferase domain and C-terminal RNA-dependent RNA polymerase domain was expressed in Escherichia coli, and RNA-dependent RNA polymerase activity was demonstrated with the purified protein. The RNA-dependent RNA polymerase assay conditions were optimized, followed by the determination of apparent Km,ATP to validate the enzyme preparation. Half maximal-inhibitory concentrations against RNA-dependent RNA polymerase activity were determined for Sofosbuvir and its active metabolite. Dasabuvir did not show detectable inhibition with the tested conditions. This is the first demonstration of the inhibition of RNA-dependent RNA polymerase activity of NS5 protein from the Kyasanur forest disease virus with small molecule inhibitors. These initial findings can potentially facilitate the discovery and development of targeted therapies for treating Kyasanur forest disease.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Doença da Floresta de Kyasanur , Animais , Humanos , Vírus da Encefalite Transmitidos por Carrapatos/genética , Haplorrinos , Índia/epidemiologia , Doença da Floresta de Kyasanur/epidemiologia , Fosfatos , Sofosbuvir/farmacologia , RNA Polimerase Dependente de RNA/metabolismo , Proteínas não Estruturais Virais/metabolismo
9.
J Aerosol Sci ; 164: 106002, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35495416

RESUMO

To understand the transmission characteristics of severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) through air, samples from different locations occupied by coronavirus disease (COVID-19) patients were analyzed. Three sampling strategies were used to understand the presence of virus in the air in different environmental conditions. In the first strategy, which involved hospital settings, air samples were collected from several areas of hospitals like COVID-intensive-care units (ICUs), nurse-stations, COVID-wards, corridors, non-COVID-wards, personal protective equipment (PPE) doffing areas, COVID rooms, out-patient (OP) corridors, mortuary, COVID casualty areas, non-COVID ICUs and doctors' rooms. Out of the 80 air samples collected from 6 hospitals from two Indian cities- Hyderabad and Mohali, 30 samples showed the presence of SARS-CoV-2 nucleic acids. In the second sampling strategy, that involved indoor settings, one or more COVID-19 patients were asked to spend a short duration of time in a closed room. Out of 17 samples, 5 samples, including 4 samples collected after the departure of three symptomatic patients from the room, showed the presence of SARS-CoV-2 nucleic acids. In the third strategy, involving indoor settings, air samples were collected from rooms of houses of home-quarantined COVID-19 patients and it was observed that SARS-CoV-2 RNA could be detected in the air in the rooms occupied by COVID-19 patients but not in the other rooms of the houses. Taken together, we observed that the air around COVID-19 patients frequently showed the presence of SARS-CoV-2 RNA in both hospital and indoor residential settings and the positivity rate was higher when 2 or more COVID-19 patients occupied the room. In hospitals, SARS-CoV-2 RNA could be detected in ICUs as well as in non-ICUs, suggesting that the viral shedding happened irrespective of the severity of the infection. This study provides evidence for the viability of SARS-CoV-2 and its long-range transport through the air. Thus, airborne transmission could be a major mode of transmission for SARS-CoV-2 and appropriate precautions need to be followed to prevent the spread of infection through the air.

10.
Nucleic Acids Res ; 48(D1): D155-D159, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31599331

RESUMO

Microsatellites are short tandem repeats of 1-6 nucleotide motifs, studied for their utility as genome markers and in forensics. Recent evidence points to the role of microsatellites in important regulatory functions, and their length polymorphisms at coding regions are linked to various neurodegenerative disorders in humans. Microsatellites show a taxon-specific enrichment in eukaryotic genomes, and their evolution remains poorly understood. Though other databases of microsatellites exist, they fall short on several fronts. MSDB (MicroSatellite DataBase) is a collection of >4 billion microsatellites from 37 680 genomes presented in a user-friendly web portal for easy, interactive analysis and visualization. This is by far the most comprehensive, annotated, updated database to access and analyze microsatellite data of multiple species. The features of MSDB enable users to explore the data as tables that can be filtered and exported, and also as interactive charts to view and compare the data of multiple species simultaneously. Its modularity and architecture permit seamless updates with new data, making it a powerful tool and useful resource to researchers working on this important class of DNA elements, particularly in context of their evolution and emerging roles in genome organization and gene regulation.


Assuntos
Bases de Dados de Ácidos Nucleicos , Repetições de Microssatélites , Genoma , Humanos , Anotação de Sequência Molecular
11.
Genome Res ; 28(12): 1852-1866, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30459214

RESUMO

One of the most important questions in regenerative biology is to unveil how and when genes change expression and trigger regeneration programs. The resetting of gene expression patterns during response to injury is governed by coordinated actions of genomic regions that control the activity of multiple sequence-specific DNA binding proteins. Using genome-wide approaches to interrogate chromatin function, we here identify the elements that regulate tissue recovery in Drosophila imaginal discs, which show a high regenerative capacity after genetically induced cell death. Our findings indicate there is global coregulation of gene expression as well as a regeneration program driven by different types of regulatory elements. Novel enhancers acting exclusively within damaged tissue cooperate with enhancers co-opted from other tissues and other developmental stages, as well as with endogenous enhancers that show increased activity after injury. Together, these enhancers host binding sites for regulatory proteins that include a core set of conserved transcription factors that control regeneration across metazoans.


Assuntos
Drosophila/fisiologia , Regulação da Expressão Gênica , Regeneração/genética , Elementos de Resposta , Animais , Cromatina/genética , Sequência Conservada , Perfilação da Expressão Gênica , Transdução de Sinais , Transcrição Gênica , Ativação Transcricional , Transcriptoma
12.
Acc Chem Res ; 53(2): 496-507, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32027125

RESUMO

Molecules and materials derived from self-assembled extended π-systems have strong and reversible optical properties, which can be modulated with external stimuli such as temperature, mechanical stress, ions, the polarity of the medium, and so on. In many cases, absorption and emission responses of self-assembled supramolecular π-systems are manifested several times higher when compared with the individual molecular building blocks. These properties of molecular assemblies encourage scientists to have a deeper understanding of their design to explore them for suitable optoelectronic applications. Therefore, it is important to bring in highly responsive optical features in π-systems, for which it is necessary to modify their structures by varying the conjugation length and by introducing donor-acceptor functional groups. Using noncovalent forces, π-systems can be put together to form assemblies of different shapes and sizes with varied optical band gaps through controlling intermolecular electronic interactions. In addition, using directional forces, it is possible to bring anisotropy to the self-assembled nanostructures, facilitating efficient exciton migration, resulting in the modulation of optical and electron-transport properties. In this Account, we mainly summarize our findings with optically tunable self-assemblies of extended π-systems such as p-phenylenevinylenes (PVs), p-phenyleneethynylenes (PEs), and diketopyrrolopyrroles (DPPs) as different stimuli-responsive platforms to develop sensors and security materials. We start with how PV self-assemblies and their coassemblies with appropriate electron-deficient systems can be used for the sensing of analytes in contact mode or in the vapor phase. For example, whereas the PV having electron-deficient terminal groups has high sensitivity toward trinitrotoluene (TNT) in contact mode, the supercoiled fibers formed by the coassembly of self-sorted stacks of C3-symmetrical PV and C3-symmetrical electron-deficient perylene bisimide are capable of sensing vapors of nitrobenzene and o-toluidine. The power of different functional groups in combination with PVs has been further illustrated by attaching CO2-sensitive tertiary amine moieties to a cyano-substituted PV, which allowed the bimodal detection of CO2 using fluorescence and Raman spectroscopy. Interestingly, the functionalization of PVs with terminal amide groups and chiral alkoxy side chains provided a mechanochromic system that allows self-erasable imaging. Whereas PVs exhibit quenching of fluorescence in most cases during self-assembly, PE derivatives exhibit aggregation-induced emission. This property of PEs has been exploited for the development of stimuli-responsive security materials, especially for currency and documents. For instance, the blue fluorescence of a PE attached to hydrophilic oxyethylene side chains coated on a filter paper upon contact with water changes to cyan emission due to the change in the molecular packing. Interestingly, the molecular packing of a Bodipy-attached PE-based gelator allowed a stress-induced change in the emission behavior, resulting in strong near-infrared (NIR) emission upon the application of mechanical stress or gelation. Finally, the use of DPP-based π-systems for the development of NIR transparent optical filters that block UV-vis light and their security- and forensic-related applications are described. These selected examples of the π-system self-assemblies provide an idea of the current status and future opportunities for scientists interested in this field of self-assembly and soft materials research.

13.
Cell Biol Int ; 45(3): 580-598, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33200434

RESUMO

The nuclear matrix (NuMat) serves as the structural framework for organizing and maintaining nuclear architecture, however, the mechanisms by which this non-chromatin compartment is constructed and regulated are poorly understood. This study presents a proteomic analysis of the NuMat isolated from cultured skeletal muscle cells in three distinct cellular states- proliferating myoblasts (MBs), terminally differentiated myotubes (MTs), and mitotically quiescent (G0) myoblasts. About 40% of the proteins identified were found to be common in the NuMat proteome of these morphologically and functionally distinct cell states. These proteins, termed as the "core NuMat," define the stable, conserved, structural constituent of the nucleus, with functions such as RNA splicing, cytoskeletal organization, and chromatin modification, while the remaining NuMat proteins showed cell-state specificity, consistent with a more dynamic and potentially regulatory function. Specifically, myoblast NuMat was enriched in cell cycle, DNA replication and repair proteins, myotube NuMat in muscle differentiation and muscle function proteins, while G0 NuMat was enriched in metabolic, transcription, and transport proteins. These findings offer a new perspective for a cell-state-specific role of nuclear architecture and spatial organization, integrated with diverse cellular processes, and implicate NuMat proteins in the control of the cell cycle, lineage commitment, and differentiation.


Assuntos
Células Musculares/metabolismo , Músculo Esquelético/citologia , Matriz Nuclear/metabolismo , Proteoma/metabolismo , Proteômica , Animais , Linhagem Celular , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Mioblastos/metabolismo , Fase de Repouso do Ciclo Celular
14.
Dev Biol ; 456(1): 74-85, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31422102

RESUMO

Proper genetic and epigenetic regulation is necessary to maintain the identity and integrity of cells. Enzymes involved in post-transcriptional modifications of histones are key factors in epigenetic mechanisms. Such modifications are also gaining importance for their role in growth and development of cancer. SETDB1 catalyzes the epigenetic mark of lysine-9 methylation of histone-3. In this study, we explored the role of SETDB1 in Drosophila hematopoiesis. We show that SETDB1 controls the differentiation of matured blood cells in wandering third instar larvae. There are three matured blood cells in wild type Drosophila melanogaster: plasmatocytes, crystal cells and lamellocytes. We found that loss-of-function mutants of SETDB1 show hematopoietic defects; increased blood cell proliferation, decreased number of crystal cells, greater differentiation of blood cells into lamellocytes, dysplasia of the anterior lobes of lymph gland and presence of hematopoietic tumors. Cell type specific knockdown of SETDB1 provided similar phenotype i.e., decreased number of crystal cells and an increase in lamellocyte differentiation. In animals with loss of function of SETDB1, Notch pathway was downregulated. Further, over-expression of SETDB1 in blood cells resulted in an increase in the number of crystal cells. This increase is accompanied with an increase in the number of NotchICD expressing cells. We therefore performed genetic rescue using UAS-GAL4 system to rescue loss of function SETDB1 mutants. Our data show that the rescued larvae carrying a wild type copy of SETDB1 in mutant background are devoid of blood tumors. We have identified a novel dual function of SETDB1 methylatransferase as a critical regulator of two of the matured hemocytes, crystal cells and lamellocytes. We propose a novel role of SETDB1 in modulating the differentiation of crystal cells and lamellocytes from a common progenitor and underscore the importance of SETDB1 in Drosophila blood tumor suppression.


Assuntos
Proteínas de Drosophila/metabolismo , Hematopoese/fisiologia , Histona-Lisina N-Metiltransferase/metabolismo , Animais , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Epigênese Genética/genética , Hematopoese/genética , Hemócitos/citologia , Histona-Lisina N-Metiltransferase/genética , Larva/metabolismo , Transdução de Sinais
15.
Dev Biol ; 446(1): 80-93, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30529058

RESUMO

Insect mushroom bodies (MB) have an ensemble of synaptic connections well-studied for their role in experience-dependent learning and several higher cognitive functions. MB requires neurotransmission for an efficient flow of information across synapses with different flexibility to meet the demand of the dynamically changing environment of an insect. Neurotransmitter transporters coordinate appropriate changes for an efficient neurotransmission at the synapse. Till date, there is no transporter reported for any of the previously known neurotransmitters in the intrinsic neurons of MB. In this study, we report a highly enriched expression of Choline Transporter (ChT) in Drosophila MB. We demonstrate that knockdown of ChT in a sub-type of MB neurons called α/ß core (α/ßc) and ϒ neurons leads to eclosion failure, peristaltic defect in larvae, and altered NMJ phenotype. These defects were neither observed on knockdown of proteins of the cholinergic locus in α/ßc and ϒ neurons nor by knockdown of ChT in cholinergic neurons. Thus, our study provides insights into non-canonical roles of ChT in MB.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Corpos Pedunculados/metabolismo , Junção Neuromuscular/metabolismo , Neurônios/metabolismo , Animais , Animais Geneticamente Modificados , Neurônios Colinérgicos/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Proteínas de Membrana Transportadoras/genética , Corpos Pedunculados/citologia , Corpos Pedunculados/crescimento & desenvolvimento , Junção Neuromuscular/genética , Junção Neuromuscular/crescimento & desenvolvimento , Pupa/genética , Pupa/crescimento & desenvolvimento , Pupa/metabolismo , Interferência de RNA , Transmissão Sináptica/genética , Transmissão Sináptica/fisiologia
16.
J Mol Evol ; 88(4): 345-360, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32166385

RESUMO

Intracellular microsporidian Nosema mylitta infects Indian wild silkworm Antheraea mylitta causing pebrine disease. Genetic structure and phylogeny of N. mylitta are analysed using nucleotide variability in 5S ribosomal DNA and intergenic spacer (IGS) sequence from 20 isolates collected from Southern, Northern and Central regions of Jharkhand State. Nucleotide diversity (π) and genetic differentiation Gst were highest in the Central isolates whereas lowest in the North. Among the isolates, absence of nucleotides, transitions and transversions were observed. Haplotyping showed nucleotide variability at 83 positions in IGS and 13 positions in 5S rDNA. Haplotype-based genetic differentiation was 0.96 to 0.97 whereas nucleotide sequence-based genetic differentiation was higher (Ks = 22.29) between Southern and Central isolates. Bottleneck analysis showed negative value for Tajima's D and other summary statistics revealing induction of loss of rare alleles and population explosion. From IGS, 17 ancestral sequences were inferred by Network algorithm. Core of nine closely related nodes having ancient nucleotides and peripheral nodes with highly divergent nucleotides were derived. Most diverged peripheral haplotype was Bero (H11) from the Central region whereas Deoghar (H3) of the Northern region diverged early. Phylogeny of N. mylitta grouped Southern and Northern isolates together revealed weak phylogenetic signal for these locations. Phylogeny of N. mylitta with Nosema sp. infecting other lepidopterans clustered N. mylitta isolates with N. antheraea and N. philosamiae of China indicating genetic similarity whereas other species were dissimilar showing diversity irrespective of country of origin.


Assuntos
Bombyx , Nosema , Animais , Sequência de Bases , Bombyx/microbiologia , China , DNA Intergênico/genética , Nosema/genética , Nucleotídeos , Filogenia , RNA Ribossômico 5S/genética , Análise de Sequência de DNA
17.
Cardiology ; 145(2): 63-70, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31910405

RESUMO

BACKGROUND: Serial increases in high-sensitivity cardiac troponin (hs-cTnT) have been associated with death in community-dwelling adults, but the association remains uninvestigated in those with coronary artery disease (CAD). METHODS: We measured hs-cTnT at baseline and after 5 years in 635 ambulatory Heart and Soul Study patients with CAD. We also performed echocardiography at rest and after treadmill exercise at baseline and after 5 years. Participants were subsequently followed for the outcome of death. We used a multivariable-adjusted Cox proportional hazards model to evaluate the association between 5-year change in hs-cTnT and subsequent all-cause mortality. RESULTS: Of the 635 subjects, there were 386 participants (61%) who had an increase in hs-cTnT levels between baseline and year 5 measurements (median increase 5.6 pg/mL, IQR 3.2-9.9 pg/mL). There were 182 deaths after a mean 4.2-year follow-up after the year 5 visit. After adjusting for clinical variables, a >50% increase in hs-cTnT between baseline and year 5 was associated with a nearly 2-fold increased risk of death from any cause (hazard ratio 1.7, 95% confidence interval 1.1-2.7). When addition of year 5 hs-cTnT was compared to a model including clinical variables and baseline hs-cTnT, there was a modest but statistically significant increase in C-statistic from 0.82 to 0.83 (p = 0.04). CONCLUSION: In ambulatory patients with CAD, serial increases in hs-cTnT over time are associated with an increased risk of death.


Assuntos
Doença da Artéria Coronariana/mortalidade , Troponina T/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Causas de Morte , Doença da Artéria Coronariana/metabolismo , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Fatores de Risco , São Francisco/epidemiologia
18.
Mol Biol Rep ; 47(4): 2889-2900, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32239465

RESUMO

Mulberry is a fast growing economically important tree for sericulture industry and contains compounds for preventing and treating several diseases and ailments. The quality and quantity of mulberry leaf available to produce silk fibre and for medicinal purpose is greatly affected by number of foliar diseases, out of which powdery mildew is the major one. Imparting genetic resistance becomes an important approach in disease management in mulberry as spraying of fungicides has harmful effects on silkworm growth and development. Deployment of non-functional susceptible genes such as Mildew resistance Locus O (MLO) against powdery mildew in few crops stimulated to identify and characterize MLO genes in mulberry. In this study, genome wide analysis identified 16 MLO genes in Morus notabilis. Phylogenetic analysis found that MnMLO2, MnMLO6A, MnMLO6B, MnMLO12A and MnMLO12B clustered with functionally characterized MLOs associated with powdery mildew susceptibility in dicot species. Gene expression analysis indicated increased transcript abundance of MnMLO2, MnMLO6A, and MnMLO12A in response to powdery mildew infection. Further, conserved motifs exclusive to functionally characterized MLOs were identified in MnMLO1C, MnMLO2 and MnMLO6A proteins. Combined analysis of the phylogenetic relationship, conserved motif analysis and gene expression in response to infection identified MnMLO2 and MnMLO6A as potential candidate genes involved in powdery mildew susceptibility in mulberry. Identification and deployment of natural and induced mutations in the candidate genes can be useful for mulberry breeding programs to develop powdery mildew resistant varieties.


Assuntos
Proteínas de Ligação a Calmodulina/genética , Resistência à Doença/genética , Morus/genética , Sequência de Aminoácidos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ascomicetos/genética , Proteínas de Ligação a Calmodulina/metabolismo , Expressão Gênica , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Morus/metabolismo , Filogenia , Doenças das Plantas/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética
19.
Mol Cell Proteomics ; 17(10): 1965-1978, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29991507

RESUMO

Chromatin condenses several folds to form mitotic chromosomes during cell division and decondenses post-mitotically to reoccupy their nuclear territory and regain their specific transcriptional profile in a precisely lineage specific manner. This necessitates that the features of nuclear architecture and DNA topology persist through mitosis. We compared the proteome of nuclease and high salt resistant fraction of interphase nucleus known as nuclear matrix (NuMat) and an equivalent biochemical fraction in the mitotic chromosome known as mitotic chromosome scaffold (MiCS). Our study elucidates that as much as 67% of the NuMat proteins are retained in the MiCS indicating that the features of nuclear architecture in interphase nucleus are retained on the mitotic chromosomes. Proteins of the NuMat/MiCS have large dynamic range of MS signal and were detected in sub-femtomolar amounts. Chromatin/RNA binding proteins with hydrolase and helicase activity are highly enriched in NuMat as well as MiCS. Although several transcription factors involved in functioning of interphase nucleus are present exclusively in NuMat, protein components responsible for assembly of membrane-less nuclear bodies are uniquely retained in MiCS. Our study clearly indicates that the features of nuclear architecture, in the structural context of NuMat, are retained in MiCS and possibly play an important role in maintenance of cell lineage specific transcriptional status during cell division and thereby, serve as components of cellular memory.


Assuntos
Cromossomos/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Mitose , Matriz Nuclear/metabolismo , Animais , Eletroforese em Gel Bidimensional , Proteoma/metabolismo , Controle de Qualidade , Espectrometria de Massas em Tandem
20.
Andrologia ; 52(4): e13551, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32124461

RESUMO

A majority of the cases of primary male infertility are idiopathic with the underlying molecular mechanisms contributing to the pathophysiology as yet unknown. Effects of the environment can alter the sperm epigenome thereby impacting male reproductive health. Epigenetic mechanisms are crucial to understanding health and disease, and methylome alterations are now known to have far-reaching clinical implications. Here, we report the results from our pilot study, a first of its kind analysis of the effect of the traditional practice of yoga on human sperm quality. We find marked improvement in sperm characteristics in patients of idiopathic male infertility following a supervised 21-day yoga regimen. Furthermore, next-generation sequencing-based methylome analysis reveals alterations in the sperm epigenome of these patients. We find that the practice of yoga is associated with DNA methylation changes at nearly 400 genes, 147 of which were hypermethylated while 229 were hypomethylated. These included promoters of several genes linked to maintenance of fertility and genomic integrity. This novel piece of work draws a direct link between positive lifestyle practices and male reproductive health.


Assuntos
Epigenoma , Infertilidade Masculina/metabolismo , Infertilidade Masculina/terapia , Espermatozoides/metabolismo , Yoga , Adulto , Humanos , Masculino , Projetos Piloto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA